1) Effect of expansion and contraction: 

Extreme temperatures cause materials to expand and contract. Your car windshield is no exception. Glass expands in hot weather and shrinks in cold weather. These constant changes can stress existing cracks or chips, causing them to spread further. Understanding this phenomenon is critical to protecting your windshield. 

Solution: Park smart - try to park your vehicle in shaded areas when possible in hot weather. Conversely, in freezing temperatures, avoid using hot water to quickly defrost the windshield, as the rapid temperature change can cause cracks. 

2) Thermal stress: 

Rapid temperature changes can cause thermal stress on the windshield, especially if you use an air conditioner or defroster. This stress can create new cracks or cause existing cracks to propagate. 

Solution: Adjust the temperature gradually - If you use an air conditioner or defroster, try adjusting the temperature gradually instead of making sudden changes. This approach reduces the thermal stress on the glass. 

3) Debris and Ice Buildup: 

Extreme temperatures can cause debris and ice to build up on your windshield, which can cause scratches or even cracks if not carefully removed. 

Solution: Remove ice and debris carefully - use a soft brush or scraper to remove ice and debris from the windshield, avoiding hard or sharp tools that can damage the glass.